Method of making sulfuric anhydrid.



- Patented D66. 25, I900. H. A. FBASCH. I

METHOD OF MAKING SULFUBIC ANHYDBID.

(Applies/aim filed. lhy 14, 1900.)

(No Model.)

UNITED STATES PATENT OFFICE.

HANS A. FRASGH, or NEW YORK, N. Y.

METHOD OF MAKING SULFURIC ANHY'DRID.

SPECIFICATION forming part of Letters Patent N 0. 664,630, dated December 25, 190 0.

Application filed May 14, 1900. S n-i 1 No. 16,638. (No specimens.)

To all whom it may concern:

Be it known that I, HANS A; FRASOH, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented a certain new and useful Method of Making Sulfuric Anhydrid, of which the following is a full, clear, and exact description.

In the manufacture of sulfuric anhydrid it has been proposed to use ferric oxid as a catalytic contact substance; and the object of the present invention is to produce and apply ferric oxid in this process.

The advantage of greater energy gained from ferric oxid freshly produced, as from iron pyrites, is known. Attempts have been made to utilize ferric oxid by accumulating a body of sulfur ore in pyrite-burners and drawing the sulfur dioxid through the body of iron cinders derived from the combustion of the sulfur; but it has been found that the temperature becomes too high for the formation of sulfuric anhydrid, and unless a large excess of air were admitted to the burners and the gases of combustion were diluted therewith no practical result was obtained.

I find that in comparison to the amount of ore burned to produce the sulfur dioxid a much smaller quantity of ferric oxid than the ore produced will sufiice to oxidize the sulfur dioxid derived from the burning of a large quantity of ore, so that I can avoid or regulate the heat produced by the combustion of the bulk of the sulfur ore by burning the ore in independent ordinary ore-burners and conducting the sulfur-dioxid gases to a converter in which only enough sulfur ore is burned to maintain the proper temperature and at the same time produce fresh ferric oxid for a contact substance. For this purpose I employ a catalytic converter, which produces the required quantity of ferric oxid for contact substance and at the same time admits of the complete regulation of the temperature in the converter by the quantity of fresh sulfur ore charged into said converter.

Having thus stated the principle of my invention, I will proceed now to describe the best mode in which I have contemplated applying that principle and then will particularly point out and distinctly claim that which constitutes my invention.

In the accompanying drawing I have shown in vertical section one form of apparatus by which my invention may be practiced.

In the drawing, a is a metallic shell suitably mounted and lined inside with fire-brick or other refractory material I), having a feedhopper c, with a suitable feed device (I, and a grate c, with a discharge-slide f, opening into a chamber g, which has a dumping device h.

t' is a hot-air inlet.

j is an inlet for the sulfur dioxid.

k is an outlet for the sulfuric anhydrid, and Zis a pyrometer.

The converter is charged with a body wt of ferric oxid, such as pyrite cinders, resting upon the grate, and the top of this body of cinders is charged with fresh pyrites (sulfur ore) and ignited by any ordinary method. The hopper, which may be a self-feeder, supplies the fresh sulfur ore. When the body of ferric oxid has been brought to the required temperature indicated by the pyrometer, sulfur dioxid is admitted from any ordinary source, such as a pyrite-burner, through the inletj, and hot air is introduced through the inlet 11 to support combustion of the sulfor on top of the oxid body. The sulfur dioxid, together with the requisite quantity of air, passing through the body of hot ferric oxid becomes oxidized and leaves the converter through the outlet is in the form of sulfuric anhydrid, which is conveyed away to be condensed or further treated in any ordinary manner. Whenever the temperature in the converter falls below the desired degree, a portion of the ferric oxid is removed from below through the grate and dischargeslide and falls into the chamber g, whence it is removed after the bottom of the converter has been closed. Sim ultaneously with the removal of the spent oxid from the bottom of the converter a fresh supply of sulfur ore falls to the top of the body of oxid and, being ignited, produces an increaseof temperature in the converter, and by this method I am enabled to regulate the degree of temperature desired in the converter, while at the same time I produce constantly fresh contact sub stance in the form of ferric oxid by the com-' drid by catalysis, which consists in burning a' ferric-oxid-prodncing substance upon a body of ferric oxid in a converter and in the presence of air, and then conducting sulfur dioXid,derived from an external source, through the converter and over the contact substance While the latter is in a state of combustion, substantially as described.

2. The method of making sulfuric anhydrid, which consists in constantly producing a fresh body of ferric oXid upon a ferric-oxid foundation, and supporting the combustion by means of hot air, and thereafter introducing sulfur dioxid and air into the burning body until oxidation is complete, and conducting away the sulfuric anhydrid and con densing the same, substantially as described.

3. The method of making sulfuric anhydrid,vthrough the medium of a ferric-oxid catalytic contact substance, which consists in burning, in a converter, a fGlIlC-OXld-PlO- ducin-g substance upon a body of ferric oxid, I V in thepresence of air, admitting sulfur dioxid thereto, and regulating the temperature 7 1 of the converter by the quantityof ferricoxid-producing substance freshly charged into the converter for the formation of addi-' tional ferric oxid for contact purposes, substantially as described.

4:: In the process of making sulfuric anhy- I drid, by means of a ferric-02nd contact-converter, regulating the temperature of theconverter by the quantity-of ferric-.oxid-producing substance charged into the same, and f thereby and simultaneously renewing the fer-' q 1 ric oxid contact substance, substantially as described.

In testimony whereof I have hereunto set; 1

my hand this 7th day of May, A. D. 1900.

HANS A. FRASGH- j '7 Witnesses:

O. E. HARTE, WM. E. WOOD. 

